There has been a long felt need for a storage system for pick-up trucks which is capable of organizing tools and small items such as nuts and bolts, electrical fixtures and the like. Pick-up trucks typically have a flat bed which provides no built-in means for organizing such items. This need to store and organize small items is particularly acute in pick-up trucks which have roof units installed over their beds. Typically, such roof units have hinged access doors positioned above the tailgate of the truck and/or above one or both of the side walls adjoining the bed of the truck. Such roof units restrict access both to the bed of the truck and, in particular, to the portion of the bed of the truck directly behind the cab making it particularly difficult to reach small items inside the truck.
For example, storage containers directly behind the cab of the truck such as that described illustrated in U.S. Pat. No. 4,288,011 are particularly inaccessible in trucks equipped with a roof unit over their beds. Because of this absence of storage space for small objects, these objects oftentimes become scattered over the bed of the truck and become even more inaccessible to an individual trying to reach them through the side openings in the roof unit. There exists a need, therefore, for a storage unit which is accessible through openings in the size of a roof unit of a pick-up truck. This unit should be sturdy and easy to assemble and should provide compartments for various small items. Preferably, the unit should also not interfere with or restrict access to the bed of the truck nor should it constrict the usable space available on the bed of the truck.